Well pump



F. E. cARLBl-:RG

WELL PUMP I Filed July 13, 1942 Nov. 3, 1942.

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Patented Nov. 3, 1942 Unirse srarss Farrar WELL PUMP.

Frank E. Carlberg, Pleasantville, lPa.

Application July 13, 1942, Serial No. 450,727

2 Claims. (Cl. 10S- 179) The present invention relates to well pumps and more particularly to working barrels or pump cylinders for use in drilled well type pumps.

One of the primary objects of the invention is to provide a pump cylinder which can be easily assembled in position and which can be easily removed for replacement.

Another important object of my invention is to provide a pump cylinder which can be made without costly machining operations.

Other objects and advantages of my invention will be apparent or will be specifically referred to hereinafter.

In pumps of the drilled well type it is customary to provide a pump cylinder or working barrel which is secured in the string of tubing extending from the surface to the bottom of the well. These pump cylinders are subject to wear caused by reciprocation of the pump piston or plunger therein. In cases where the pumped fluid contains abrasive or corrosive substances, the pump cylinders must be replaced at more or less frequent intervals. In those cases where the pumped fluid contains corrosive substances, there often is considerable diiculty in removing the worn pump cylinder due to corrosive effects. My invention overcomes this difficulty.

The pump cylinders must be rigidly secured in position during operation of the pump. This need has heretofore made it necessary to subject the metal from which the cylinder is made to costly machining operations in order that means would be available for anchoring the cylinder in position. I eliminate this diculty by providing a pump cylinder which only need be cut to appropriate length and exteriorly threaded at one end. The metal stock for making the cylinders, therefore, may be manufactured in long tubes which are finished at the mill.

It is necessary for drilled well type pumps to be provided with a standing valve at or near the lower end of the pump cylinder. An important feature of my invention resides in the provision of a special type coupling which forms a support for the standing valve and which cooperates with a section of the well tubing to clamp the pump cylinder in position.

For a more detailed description of my invention reference is made to the attached drawing wherein:

Figure 1 is a longitudinal sectional View of a pump embodying my invention, and

Figure 2 is a transverse sectional view looking in the direction of the arrows along line 2 2 of Fig. 1.

CII

The reference numeral 3 designates generally a string of well tubing composed of the sections 4 and 5, which are joined together by means of a coupling At the lower end of the tube section 5 there is provided a special type of coupling, designated generally by the reference numeral 1, which joinsl the tube section 5 to the anchor 8. The coupling 'I is provided with an inwardly extending annular flange 9 which forms a support for the standing valve designated in its entirety by the reference numeral I0. It will be noted that the coupling 'l is in threaded engagement with the tube section 5, as indicatedV by numeral II.

Within the tube section 5 is a pump cylinder I2. The lower end of the pump cylinder I2 is exteriorly threaded as indicated by reference numeral I3. An interiorly threaded annular collar Il! is secured to the pump cylinder l2 by means of the threads I3. -The annular collar I4 is somewhat largerin outside diameter than the inside diameter of the tube section 5 but is slightly smaller in outside diameter than the outside diameter of the tube section 5. This annular collar, therefore, is capable of being clamped between the lower end 5a of the tube section 5 and the inwardly extending flange 9 of the coupling?, as is clearly shown in Fig. 1. It should be distinctly noted Ythat the outer periphery of the collar I4 isnot in threaded engagement with the coupling 1. By the arrangement just described the pump cylinder is properly centered and rmly secured within the well tubing.

In those cases where the uid is to be pumped I contains corrosive substances, I have found it advisable to provide a packing around the pump cylinder at or near the upper end thereof to prevent corroslve fluids from contacting the elements constituting the means for securing the pump cylinder in position. Such a packing is designated by the reference numeral I5 and is in the form of a ring of flexible material which surrounds the upper end of the pump cylinder. This packing is compressed between the upper end 5b of the tube section 5 and the lower end 4a of the tube section 4. In being so compressed, the packing I5 is forced into sealing engagement with the outer surface of the pump cylinder and thus prevents fluid from access to the space I6 around the outer wall of the cylinder. l

It will 4be noted that the inwardly extending ange 9 on the coupling 'I forms a central aperture IS which is frusto-conical, when viewed in section as in Fig. 1. The standing valve II! is provided with a complementary frusto-conical base I9 which is received within the aperture I8. In all other respects the standing valve may be conventional in form and for that reason it is not described in detail. Similarly the pump plunger or piston 2i) may be of any desired construction.

Improvements in the art of metal working have made it possible for long tubes having a polished inside iinish to be made and tempered without costly machining operations. In the practice of my invention it is possible to purchase such tubing and to cut off a length appropriate for use as a pump cylinder in any particular pump. Due to diiferences in production characteristics of various wells, particularly oil wells, it is customary to use pumps having diierent pumping strokes. Thus, it will be seen that there is a distinct advantage in purchasing long finished tubing and cutting such tubing into appropriate lengths rather than maintaining a large stock of pump cylinders in different lengths. After the appropriate length is cut from the tubing, the severed portion requires nothing more than a thread cutting operation at one end thereof. This can be done in the eld Without expensive equipment. The thread cutting operation does not destroy the tempering of the metal which is an important consideration.` After threading, the annular collar I4 is tightly secured onto the pump cylinder and the cylinder is inserted Within a section of well tubing, such as section 5 shown in Fig. 1. The coupling 1 is then threaded onto the section 5 and tightened so that the collar I4 is tightly clamped into position. The packing I5 is then placed around the opposite end of the pump cylinder and the tube section 4 and coupling 5 are assembled in a manner to compress the packing into sealing engagement with the outer surface of the pump cylinder.

When it is desired to remove the pump cylinder I2 for replacement, the coupling 'I is unscrewed from the tube section 5. Under ordinary-circumstances the unscrewing of the coupling 1 will merely release the clamping actiony on collar I4 and the collar and cylinder may be readily withdrawn from the tubing. In the event that corrosion has occurred between the outer periphery of the collar I4 and the inner surface of the coupling '1, the collar may be unscrewed from the pump cylinder I2 during turning of the coupling 'I. There is no serious objection to this possibility since the pump cylinder I2 may be readily removed from the tubing and the collar I4 may then be easily removed from the coupling. Thus it will be seen that there is a possible double break or zone of separation when the pump assembly is dismantled for removal of the cylinder. Obviously, it will facilitate removal of the pump cylinder from the tubing if the compression is released from the packing I5.

The inwardly extending ange S performs the dual function of providing a support for the standing valve I0 and cooperating with the lowed end 5a of the tube section E to clamp the pump cylinder I2 in position.

The foregoing specific description is for the purpose of illlustration only and it will be understood that various obvious modifications may be resorted to without departing from the scope of the invention as defined by the following claims. Having described the invention, I claim:

1. In a pump assembly for use in drilled wells, a string of tubing made up from a plurality of tube sections externally threaded at their ends and coupled with internally threaded couplings,

' a pump cylinder within said string of tubing, one

end of said cylinder being externally threaded and provided with an internally threaded annular collar, said collar being clamped between an end of one of said tube sections and an inwardly extending flange on the cooperating coupling, and said cylinder being surrounded by a flexible annular packing which is compressed into sealing contact with the outer wall of said cylinder by opposed ends of two of said tube sections at a coupling spaced from that coupling having the said inwardly extending flange, whereby said cylinder is rmly supported within said string of tubing and is readily removable upon separation of said couplings.

2. In a pump assembly for use in drilled wells, a string of tubing made up from a plurality of `tube sections externally threaded at their ends and coupled with internally threaded couplings, one of said couplings being provided with an inwardly extending flange, a standing valve supported by said'inwardly extending flange, a pump cylinder within said string of tubing, one end of said cylinder having an outwardly extending annular collar threadedly secured thereto, said collar being clamped between an end of one of said tube sections and said inwardly extending flange to thereby rigidly secure said pump cylinder in position within said string of tubing.

FRANK E. CARLBERG. 

